<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>分支语句</title>
</head>
<body>
    <script>
        if(9>1){
            console.log('ok')
        }
        if(20>2){
            console.log('20')
        }else{
            console.log('2')
        }
        var grade = 82
        if(grade >= 90){
            console.log('你很棒')
        }else if(grade >= 80){
            console.log('你依旧很棒')
        }else{
            console.log('你、')
        }
    </script>

</body>
</html>